Sony has started rolling out a new firmware update in the form of build version 12.0.A.2.245 with Android 4.1.2 software update for Xperia SP handsets. The update is rolling out to HSPA+ (C5302) and LTE (C5303) handsets. It’s a global update rolling in every region and it is coming on both versions of Xperia SP.
The update has brought a new UI and some other cool features to Sony Xperia SP. The notable changes this update brings is a transparent notification bar/menu bar, an additional row of settings in the notification panel and some new Small Apps. A quick settings menu is also available on the notification shade. The changelog also includes an improved camera, mainly in terms of low-light performance and many bug fixes.
Update is now rolling out worldwide to the international 3G and LTE versions of the Xperia SP, it might take few days to come to your Xperia SP.[Source 1] [Source 2]